5 Knob Deej Box

A simple 5-knob deej box that talks to deej on Windows. Printed in two parts with 3mm heat-set inserts . Uses an ATmega32U4 Pro Micro so the PC sees it as a USB device. I am including the top and bottom case pieces in the print profile. Knobs are from another MakerWorld user and linked below.

What’s included

• Case Top STL
• Case Bottom STL
• Print profile for both parts
• Link to the knobs I used: Knobs

Hardware

• 1x Pro Micro ATmega32U4 5V 16 MHz (micro USB)
• 5x 10k linear potentiometers (panel mount)
• 5x knobs (see link above)
• M3 heat-set inserts and M3x6 screws, or small self-tapping screws
• Hookup wire, solder

Wiring

• All pot left legs to GND, all right legs to 5V
• Wipers to A0, A1, A2, A3, and A6
• A6 lives on pad 4 on a Pro Micro. If your board labels only numbers, use pad 4 and read it as A6 in code.
• Common ground between all pots and the board

Firmware notes

Use the deej Arduino sketch for ATmega32U4. If A6 looks dead, install the SparkFun AVR Boards core and select SparkFun Pro Micro 5V 16 MHz, or add a small throwaway read between channels to remove ghosting.

Assembly

1. Press or install heat-set inserts in the top
2. Mount the five pots in the top and solder the wiring
3. Seat the Pro Micro, strain-relief the USB lead, I used some hot glue
4. Close the case and add the knobs
5. Flash the sketch, run deej, and test

Notes

• If your bootloader is fussy, double-tap reset to enter bootloader, or reflash Caterina once and uploads will be painless
• Add 0.01-0.1 µF caps from each wiper to GND if you want ultra-smooth readings

Credits: knobs by Narvick.